Cast-off friction for sewing-machines.



PATENTED JULY 7, 1908.

M. D. HEBBRT'. CAST-OFF FRICTION FOR SEWING MACHINES.

APPLICATION FILED FEB. 29. 1908.

2 SHBETSSHEET 1.

WITNEEEIEE No. 892,958. PATENTED JULY 7, 1908.

M. D. HBBERT.

CAST-OFF FRICTION FOR SEWING MACHINES.

APPLICATION FILED FEB. 29. 190B.

2 S HEETSSHEET 2.

\A/ITNEEEEE MADOR D. HEBERT, OF GLOVERSVILLE, NFAV YORK.

CAST-OFF FRICTION FOR SEWING-MACHINES.

Specification of Letters Patent.

Patented July '7, 1908.

Application filed February 29, 1908. Serial No. 418,435.

To all whom it may concern:

Be it known that I, Manon D. HEBERT, a citizen of the United States, residing at Gloversville, county of Fulton, and State of New York, have invented certain new and useful Improvements in Cast-off Frictions for Sewin -Machines, of which the following is a specification.

The invention relates to such improvements and consists of the novel construction and combination of parts hereinafter described and subsequently claimed.

Reference may be had to the accompanying drawings, and the reference characters marked thereon, which form a part of this specification. Similar characters refer to similar parts in the several figures therein.

Figure 1 of the drawings is a view in elevation of the end of a wax-thread sewing machine adjacent to the stitch-forming mechanism, the arm or head of the machine being broken away. Fig. 2 is a similar view of the same seen from .the opposite side to that shown in Fig. 1. Fig. 3 is a horizontal cross-section taken on the broken line 3-3 in Fig. 1. Fig. 4 is a vertical cross-section taken on the broken line 4-4l in Fig. 3, through the needle-bar and cast-off bar. Fig. 5 is a view in perspective of the frictionplate for the cast-off bar. Fig. 6 is a view in perspective of the adjustable member of a clamp, between the members of which the cast-off friction-plate moves. Fig. 7 is a view in perspective of the other member of said clamp and the supporting bracket therefor. Fig. 8 is a view in perspective of one of the friction-pads adapted to be forced by the members of the clamp against the opposite sides of the cast-off friction-plate. Fig. 9 is a horizontal cross-section taken on the broken line 99 in Fig. 2. Fig. 10 is a horizontal cross-section taken on the broken line l010 in Fig. 4, through the needle and grooved end of the cast-off.

The present invention relates to the castoff mechanism of machines for sewing leather, as in making heavy leather gloves, and the principal type of machine to which these improvements more particularly relate is known in the trade as the Boston machine.

The principal object of the invention is to render more certain and accurate, the operation of the cast-off.

features of construction and operation thereof, as are necessary to a full understanding of the present invention.

The machine is adapted for forming a chain-stitch with a single thread which, after being waxed or tarred, is supplied to the stitch-forming mechanism.

The needle, 1, which is fixed upon a needlebar, 2, beneath the throat-plate and is reciprocated in a vertical line, is formed with a barb or hook to which the thread is fed, when the needle is in its uppermost position, by the feed-hook or arm, 3, which is vibratory in a horizontal plane and is provided in its end with an eye to carry the thread. The loop or stitch of thread thus fed to the needle is drawn down through the fabric as the neodle descends.

At each successive u ward movement of the needle through the eather or fabric the last previously formed loop or stitch is left projecting below the fabric and the new loop is drawn down therethrough as the needle next descends, the previously formed loop being prevented from engaging the hook or beard of the needle by means of the cast-oil 4.

Simultaneously with each downward movement of the needle an aperture is formed by a downward movement of the awl, 5, through the fabric at the point where it is intended the needle should pass at its next upward movement, and before such next upward movement of the needle occurs, the position of the fabric is shifted by means of the feeding mechanism so as to bring said aperture in line with the needle.

The awl-bar, 6, and the foot-bar, 7, reci rocate vertically in a face-plate, 8, movab T mounted upon the arm or head of the machine, to which face plate reciprocatory movements are imparted corresponding sub stantially in time and amplitude with the reciprocatory movements of the feed 9.

The general features of construction and manner of operation of the parts thus far described are old and well understood so that further description of the same at this point is deemed unnecessary.

The needle-bar, 2, and cast-off bar both reciprocate in vertical lines in slideways or bearings in a stationary post, 11, at the front end of the machine.

The vertical movements of the needle and needle-bar are accomplished by means of the linlcconnection, 12, between the needle-bar and the crank or rocker-arm, 13, on the gether can be varied as desired.

' vertical plane,

rock-shaft, 1 1, which rock-shaft is connected with the main shaft of the machine in the usual manner (not shown).

The cast-off bar is operated at certain. times by the needle-bar, 2, by means of an arm, 15, offset therefrom and adapted to lay between two offsets or sleeves, 16, on the cast-off bar, said sleeves being separated sufliciently to afford the requisite amount of ltpst motion in theoperation of the cast-off To maintain the cast-off bar in stationary position except while being forcibly operated by means of the needle-bar, as set forth, I provide the same with a sheet-metal friction-plate, 17, having a portion thereof bent to form integral therewith a loop, 18, adapted to receive the cast-off bar, 10, and be clamped firmly thereupon by means of a setscrew, 19, passing through an aperture in a block, 20, inserted between, and riveted to, the ends of the plate, 17, as shown in Figs. 3 and 5. Thefriction-plate is thus firmly secured upon the cast-off bar so as to accom pany' the latter in its reciprocating move ments.

The friction-plate, 17, is interposed and adapted to slide between a pair of damp members, 21 and 22, the member, 21, being fixed upon a bracket, 23, attached to the base of the stationary post, 11, by means of a screw 24.

The olampanembers are adapted to be yieldingly forced together by means of a coil-spring, 25, inclosing a screw-threaded bolt, 26, inserted through apertures in the respective clamp-members, 21 and 22, the head of the bolt being adapted to engage the outer side of the clamp-member, 22, while the spring bears upon the outer side of the clamp-member, 21 against which it is held by the nut, 27, on the outer end of the bolt 26. By adjustment of the nut, 27,the force with which the clamp-members are drawn to- T he clamp pair of friction-pads thus formed supports a to embrace thereor blocks, 28, adapted between, and be forced against the opposite sides of, the friction-plate 17. The pads or blocks, 28, may be made of leather or other suitable material.

The friction-plate, 17, being flat and presenting plane surfaces to the friction-pads or blocks, 28, is always maintained in the same and said friction-plate is so connected with the cast-off bar as to preclude rocking movement of the castoif bar in its slideway bearings, so that my im proved friction device not only secures accurate and precise operation of the cast-off with regard to its vertical position, but with regard to its rotative position as well.

As a further means for supporting and steadying the castoff in its operation, I have provided an Lshaped guide or clip, 30,

adapted to engage directly the upper end of the cast-off to insure the proper contact of the same with the needle at all times, the end of the cast-off being formed with a vertical groove, 33, to receive the needle.

The clip, 30, is adjustably secured to the post, 11, of the frame of the machine by a screw, 31, inserted through a slot, 32, in the shank of the clip, whereby the cast-off can be held against the needle with any desired degree 'of pressure; and the needle being embraced by the walls of the vertical groove, 33, in the cast-off, the needle and cast-off afford mutual support to one another, and both are steadied in their operation and maintained in their proper relative relations to each other.

The stud or post, 35, on the clamp-member, 21, serves as a fixed support and fulcrum for one end of the clamp-member, 22, as the clamp-members are drawn together by the force of the spring 25.

The clamp-members, 21 and 22, are preferably of channeled form, as shown, the member, 21, being preferably formed in an integral casting wlth the bracket, 23, while the member, 22, may be struck up from sheetmetal and adapted to be received between the side flanges of the channeled member 21.

The needle-bar, 2, is formed with a longitudinal groove, 37, adapted to receive and form a slideway for the neighboring edge of the cast-ofi, 4, which is in the form of a thin plate adapted to play in said groove, whereby the needle-bar and cast-off mutually support and steady each other. I

The manner in which the cast-off is thus supported not only insures the proper locating of the point of the cast-off with reference to the needle, but also insures the locating of thedoast-off accurately within the slot in the fee The tension device being automatic in its action upon the friction-plate connected with the cast-off bar, no lost motion can result from wear, so that the device is adapted for continued use for a long period without im pairment of its efficiency.

What I claim as new and desire to secure by Letters Patent is 1. In a machine of the class described, the combination with the reciprocatory needlebar; means for reciprocating the same; the reciprocatory cast-oif bar; and lost-motion connections between said needle-bar and cast-off bar whereby the latter is operated at certain times; of a sheet-metal plate having a portion thereof bent to form a loop to re ceive the cast-off bar; means for securing the cast-ofi bar within said loop; and a pair of friction-blocks embracing between them said friction-plate.

2. In a machine of the class described, the combination with the reciprocatory needlebar means for reciprocating the same the reciprocatory cast-off bar; and lost-motion connections between said needle bar and cast-ofi bar whereby the latter is operated at certain times; of a friction-plate having a portion thereof bent to form a loop adapted to receive the cast-off bar; a block interposed between the ends of said bent portion of the plate and secured thereto; a set screw inserted through an aperture in said block into engagement with the cast-off bar; and a pair of friction-blocks embracing between them a flat portion of said plate.

3. In a machine of the class described, the combination with the reciprocatory cast-off bar; and lost-motion mechanism for operating said bar at certain times; of a frictionplate mounted upon said cast-off bar; a pair of clamp-members, one mounted upon a stationary part of the machine; a spring for forcing toward said member the other clampmember; and friction-blocks interposed be tween said clamp-members and adapted to engage the opposite sides of said frictionplate.

4. In a machine of the class described, the combination with the reciprocatory needlebar provided with a longitudinal groove; of a cast-off having a portion thereof adapted to occupy and move along said groove; means for reciprocating said cast-ofi'; and a guide adjustably mounted upon the frame of the machine engageable with the upper end of the cast-oil. v

5. In a machine of the class described, the combination with the needle-bar provided with a longitudinal groove; and the needle of the cast-off grooved to receive the needle, and having a portion adapted to occupy and move along said groove in the needle-bar; means for reciprocating said bar; and a guide adjustably mounted upon the frame of the machine engageable with the cast-ofl.

In testimony whereof, I have hereunto set my hand this 21st day of February, 1908.

' MADOR D. HEBERT.

Witnesses:

Gno. HEBERT W. L. WELSH. 

